Different compounds in marijuana have been shown to help relieve pain and nausea, reduce inflammation, and can act as an antioxidant. Cannabidiol (CBD) can help treat seizures, can reduce anxiety and paranoia. Marijuana is helpful in treating nausea and vomiting from cancer chemotherapy. Studies have long shown that people who took marijuana extracts in clinical trials tended to need less pain medicine. More recently, scientists reported that THC and other cannabinoids such as CBD slow growth and/or cause death in certain types of cancer cells growing in laboratory dishes. Some animal studies also suggest certain cannabinoids may slow growth and reduce spread of some forms of cancer.

Individuals with prostate cancer who are finding it difficult to control certain symptoms that may be experienced as a result of the disease or treatment with standard therapies (such as pain, cachexia [“wasting syndrome”], anorexia [the symptom, not the disorder “anorexia nervosa”], nausea, and vomiting) may experience some relief through the use of whole-plant cannabis or the approved cannabinoid medication like dronabinol (i.e. synthetic THC; treatment with dronabinol has sometimes been associated with high levels of anxiety in patients, due to the absence of other cannabinoids to dull the impact of THC’s psychoactive effects). Whole-plant cannabis use should be carefully discussed with and monitored by a healthcare professional, and individuals using whole-plant cannabis should not expect that use will prevent or treat prostate cancer.